3D Extrusion
NEW (BETTER)
Solid models are constructed by
the boundary representation (B-rep) method or by constructive solid geometry
(CSG). The solid entities of CSG modeling are box, cone, sphere, cylinder,
prism, wedge and torus. CSG modeling constrcts solid models thori=ough Boolean
operations(union, subtraction and intersection) on solid entities. But in
extrusion, a 3D solid is created by extruding the face in a direction perpendicular
to it as shown in figure 5.10.
(Cad/Cam: Concepts And
Applications, Alavala, pg. 128)
OLD
Simple 3-D objects can be created
by extruding 2-D images in the third dimension. The extrusion thickness can be
specified by an appropriate command. The objects extruded will have uniform
thickness in the Z direction.
(P. Radhakrishnan, CAD/CAM/CIM,
p.147)
Cottrell
Atmosphere
NEW(BETTER)
In alloys, foreign atoms solved
in the matrix essentially determine the dislocation mobility. The solute atoms
can either be placed on the regular lattice sites to form a substitutional
alloy, or they are situated on interstitial sites. In both cases, the defect
can be approximated by a spherical elastic inclusion as done for intrinsic point
defects. The force the displaced solute atmosphere exerts on the location is
equal to that the dislocation exerts in the atmosphere. Thus, the atmosphere is
driven to move with the dislocation. The respective diffusion problem is a very
complex two-dimensional one. It was first attacked by Cottrell and Jawson. The
effect is therefore called Cottrell effect and the solute cloud Cottrell atmosphere.
(Springer series in materials
science, “no author defined”, pg 146)
OLD
Segregation of interstitial
solutes at edge dislocations accompanied by a decrease of the overall elastic
strain energy due to the fact that the lattice distortions associated with the
solute atoms are partially compensated by the lattice distortions associated
with the dislocations. Cottrell atmosphere is called condensed if the solute
atoms form a continuous string along the dislocation line. The solute
concentration necessary to produce condensed atmospheres at all the
dislocations is∼10^-4 at% at the dislocation density ∼10^10
cm–2.
(Materials of Science, Vladimir
Novikov, pg 43)
Quantity Production
NEW(BETTER)
Quantity production involves the
mass production of single parts on fairly standard machine tools such as punch
presses, injection molding machines, and automatic screw machines. These
standard machines have been adapted to the production of the particular part by
means of special tool-die sets, molds, and form cutting tools, repectively,
each designed for the part in question. The production equipment is devoted
full time to satisfying very large demand rate for the item. In mass
production, the demand rate and the production rate are approximately equal.
Examples of items in quantity production include components for assembled
products that have high demand rates (automobiles, some household appliances,
light bulbs, etc.), hardware items (such as screws, nuts, and nails), and many
plastic molded products.
(Computerized Manufacturing
Process Planning Systems; Hong-Chao Zhang, Leo Alting; page 7)
OLD
Quantity production involves the
mass production of single parts on single pieces of equipment. It typically
involves standard machines (such as stamping presses) equipped with special
tooling (e.g., dies and material handling devices), in effect dedicating the
equipment to the production of one part type. Typical layouts used in quantity
production are the process layout and cellular layout.
(Groover M. P., Fundamentals of
modern manufacturing: Materials, processes and systems, p. 19)
Automated manufacturing systems
NEW
An automated manufacturing system
usually includes machine tools for machining or forming materials, but other
machines, such as those for cleaning, assembly and painting of the product are
also included. To run the system, Computer-Aided Plannig (CAP), and other
computer based tools are applied.
Two main types of automated
manufacturing production systems can be distinguished: Dedicated Manufacturing Production Systems
(DMPS) and Flexible Manufacturing Production Systems (FMPS) or simply Flexible
Manufacturing Systems.
A dedicated manufacturing
production system is an automated system designed for the production of one
product only, and which cannot readily be adapted for the production of other products.
A flexible manufacturing system
is an automated system which capable of producing any of a range or family of
products, with a minimum amount of manual intervention. The flexibility is usually restricted to the
family of products for which the system was designed.
(Computerized Manufacturing
Process Planning Systems; Hong-Chao Zhang, Leo Alting; page 10)
OLD(BETTER)
Automated manufacturing systems
operate in the factory on the physical product. They perform operations such as
processing, assembly, inspection, or material handling, in some cases
accomplishing more than one of these operations in the same system. They are
called automated because they perform their operations with a reduced level of
human participation compared with the corresponding manual process. In some
highly automated systems, there is virtually no human participation. Examples
of automated manufacturing systems include:
• automated machine tools that
process parts
• transfer lines that perform a
series of machining operations
• automated assembly systems
• manufacturing systems that use
industrial robots to perform processing or assernblyoperations
• automatic material handling and
storage systems to integrate manufacturing operations
• automatic inspection systems
for quality control
Automated manufacturing systems
can be classified into three basic types:
(1) fixed automation. (2)
programmable automation, and (3) flexible automation.
(Mikell P. Groover, Automation,
Production Systems, and Computer-Integrated Manufacturing (2nd Edition)Systems,
pg.10)
Imbalanced Rotor
NEW
An imbalanced rotor is the most
significant source of vibration energy and provides the forcing for all other
vibration on the support structure and foundation. Therefore, the pedestal
supports flex to absorb the vibration energy sourced by the rotor, thus the
rotor does not “bounce” in the bearing, but components attached to the pedestal
supports will vibrate in a forced and in some cases a resonant manner. In this
way, by measuring and analyzing the vibrations of the supports, it is possible
to detect whether the rotor is affected by unbalancing.
(Distributed Computing,
Artificial Intelligence, Bioinformatics, Soft Computing and Ambient Assisted
Living; Sigeru Omatu, Miguel P. Rocha, José Bravo, page 1198)
OLD(BETTER)
Many
applications can be modeled as a rigid body rotating about fixed axis. In
particular driveshafts in automobiles and turbomachinery.If the rigid body is
baanced than the axis of rotation corresponds to aprincipal axis of a rigid
body.An imbalance is said to occur in situations where either or both of Ixy
and/or Iyz are non zero.The şmbalance is common feature of wheel assemblies on
cars and it is typically to add weights which usually range from 0.01kgs to
0.15kgs onto the rims of the wheels to reduce this imbalance.(Engineering
Dynamics: A Primer,Oliver M. O'Reilly,p:189)
ent� �
i t P �3 g; Sigeru Omatu, Miguel P. Rocha, José Bravo, page 1198)
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